The oxygen evolution reaction (OER) during alkaline water electrolysis is the bottleneck of water splitting. Perovskite materials have been particularly proposed as good and economically reasonable ...electrocatalysts for the OER, showing promise and advantages with respect to classic metallic electrodes. However, the degradation of perovskites during catalysis limits their service lifetime. Recently, the material BaCo0.98Ti0.02O3−δ:Co3O4 was shown to be electrocatalytically and chemically stable during water electrolysis even under industrially relevant conditions. The lifetime of this perovskite-based system is prolonged by a factor of 10 in comparison to that of Pr0.2Ba0.8CoO3−δ and is comparable to that of industrially applied electrodes. Here we report on the degradation kinetics of several OER catalysts at room temperature, comparatively studied by monitoring the oxygen evolution at microelectrodes. A decrease in the reaction rate within a maximum of 60 s is observed, which is related to chemical and/or structural changes at the oxide surface.
Pr0.2Ba0.8CoO3-δ (PBCO) and Ba0.5Sr0.5Co0.5Fe0.5O3-δ (BSCF) perovskite thin film electrodes were used as model systems for testing degradation and stability during oxygen evolution reaction (OER) in ...alkaline water electrolysis. The catalyst films were prepared by chemical solution deposition (CSD) and are binder-free. Stepwise aging experiments illustrate a systematical approach to different degrees of degradation of the perovskites after defined testing cycles of cyclic voltammetry in application-near conditions. XPS and EDX characterization at each aging step enables a monitoring of the change in chemical composition during degradation. XPS analysis points to a change in the defect chemistry of PBCO during degradation. The influence of all monitored parameters on the overall electrode service lifetime is shown in a novel end of service life test (ESLT) at thin film perovskite electrodes of 100nm thickness.
We have studied the growth of CeO
2
thin films by molecular beam epitaxy on
r
-cut sapphire substrates. The oxidation state of the substrate surface controls the growth direction of CeO
2
. Oxygen ...pre-annealed substrates favor (001) growth, while oxygen vacancies lead to a mixed (001) and (111) orientation. Combining pre- and post-annealing, it is possible to achieve single- oriented CeO
2
in both growth directions. Furthermore, post-annealing results in a dramatic increase of crystallinity with a rocking curve width of the (002) reflection as small as 0.004°. We provide a consistent growth model involving oxygen vacancies at the substrate to thin film interface.
•Patients with favorable prognostic factors are selected for robot-assisted surgery.•Open and robot-assisted radical cystectomy show similar survival outcomes.•This study supports 5years oncological ...safety of robot-assisted radical cystectomy.
Radical cystectomy with pelvic lymph node dissection is the recommended treatment in non-metastatic muscle-invasive bladder cancer (MIBC). In randomised trials, robot-assisted radical cystectomy (RARC) showed non-inferior short-term oncological outcomes compared with open radical cystectomy (ORC). Data on intermediate and long-term oncological outcomes of RARC are limited.
To assess the intermediate-term overall survival (OS) and recurrence-free survival (RFS) of patients with MIBC and high-risk non-MIBC (NMIBC) who underwent ORC versus RARC in clinical practice.
A nationwide retrospective study in 19 Dutch hospitals including patients with MIBC and high-risk NMIBC treated by ORC (n = 1086) or RARC (n = 386) between January 1, 2012 and December 31, 2015. Primary and secondary outcome measures were median OS and RFS, respectively. Survival outcomes were estimated using Kaplan-Meier curves. A multivariable Cox regression model was developed to adjust for possible confounders and to assess prognostic factors for survival including clinical variables, clinical and pathological disease stage, neoadjuvant therapy and surgical margin status.
The median follow-up was 5.1 years (95% confidence interval (95%CI 5.0–5.2). The median OS after ORC was 5.0 years (95%CI 4.3–5.6) versus 5.8 years after RARC (95%CI 5.1–6.5). The median RFS was 3.8 years (95%CI 3.1–4.5) after ORC versus 5.0 years after RARC (95%CI 3.9–6.0). After multivariable adjustment, the hazard ratio for OS was 1.00 (95%CI 0.84–1.20) and for RFS 1.08 (95%CI 0.91–1.27) of ORC versus RARC. Patients who underwent ORC were older, had higher preoperative serum creatinine levels and more advanced clinical and pathological disease stage.
ORC and RARC resulted in similar intermediate-term OS and RFS in a cohort of almost 1500 MIBC and high-risk NMIBC.
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Lymphocytic alveolitis portends a poor prognosis in human immunodeficiency virus (HIV)-infected subjects. Because alveolar lymphocytes consist predominantly of HIV-specific CD8(+) cytotoxic T ...lymphocytes (CTL), they could represent an appropriate immune response to infected cells in the lung, and be a surrogate marker for a high pulmonary viral burden. We assessed long-term outcome in a cohort of asymptomatic HIV-infected subjects who underwent bronchoscopy between 1990 and 1993 and had bronchoalveolar lavage fluid (BALF) available for determination of viral load by reverse transcription-polymerase chain reaction. The ability to detect HIV in BALF increased with disease progression. Lymphocytic alveolitis, although present at all stages of HIV infection, was most pronounced in patients with middle stage disease. The HIV viral load as measured by bronchoalveolar lavage correlated with the percentage of alveolar lymphocytes in patients with peripheral blood CD4(+) cell counts above 200/microliter. Including patients with CD4(+) cell counts < 200/microliter weakened this correlation, possibly because of replacement of CD8(+) CTL by CD8(+) suppressor cells in advanced disease. Free virus in BALF was a stronger predictor of HIV disease progression than was lymphocytic alveolitis. These data suggest that lymphocytic alveolitis in HIV-infected subjects occurs in response to viral antigens in the lung and that the poor prognosis associated with lymphocytic alveolitis reflects a high pulmonary viral burden.
Abstract Background Genomic analyses have suggested that the LPA gene and its associated plasma biomarker, lipoprotein(a) (Lpa), represent a causal risk factor for coronary heart disease (CHD). As ...such, lowering Lp(a) levels has emerged as a therapeutic strategy. Beyond target identification, human genetics may contribute to the development of new therapies by defining the full spectrum of beneficial and adverse consequences and by developing a dose–response curve of target perturbation. Objectives The goal of this study was to establish the full phenotypic impact of LPA gene variation and to estimate a dose–response curve between genetically altered plasma Lp(a) and risk for CHD. Methods We leveraged genetic variants at the LPA gene from 3 data sources: individual-level data from 112,338 participants in the U.K. Biobank; summary association results from large-scale genome-wide association studies; and LPA gene sequencing results from case subjects with CHD and control subjects free of CHD. Results One SD genetically lowered Lp(a) level was associated with a 29% lower risk of CHD (odds ratio OR: 0.71; 95% confidence interval CI: 0.69 to 0.73), a 31% lower risk of peripheral vascular disease (OR: 0.69; 95% CI: 0.59 to 0.80), a 13% lower risk of stroke (OR: 0.87; 95% CI: 0.79 to 0.96), a 17% lower risk of heart failure (OR: 0.83; 95% CI: 0.73 to 0.94), and a 37% lower risk of aortic stenosis (OR: 0.63; 95% CI: 0.47 to 0.83). We observed no association with 31 other disorders, including type 2 diabetes and cancer. Variants that led to gain of LPA gene function increased the risk for CHD, whereas those that led to loss of gene function reduced the CHD risk. Conclusions Beyond CHD, genetically lowered Lp(a) levels are associated with a lower risk of peripheral vascular disease, stroke, heart failure, and aortic stenosis. As such, pharmacological lowering of plasma Lp(a) may influence a range of atherosclerosis-related diseases.
Clonal hematopoiesis results from somatic mutations in cancer driver genes in hematopoietic stem cells. We sought to identify novel drivers of clonal expansion using an unbiased analysis of ...sequencing data from 84,683 persons and identified common mutations in the 5-methylcytosine reader,
, as well as in
,
, and
. We also identified these mutations at low frequency in myelodysplastic syndrome patients.
edited mouse hematopoietic stem and progenitor cells exhibited a competitive advantage
and increased genome-wide intron retention.
mutations potentially link DNA methylation and RNA splicing, the two most commonly mutated pathways in clonal hematopoiesis and MDS.
Background Esophageal self-expandable stents (SESs) effectively treat strictures and leaks but may be complicated by a stent-associated esophagorespiratory fistula (SERF). Little is known about ...SERFs. Objective To determine the incidence, morbidity, mortality, and risk factors for SERF. Design Retrospective case-control study. Setting Single referral center. Patients All adults undergoing esophageal SES placement during a 10-year period. Intervention Stent placement. Main Outcome Measurements Occurrence of SERF, morbidity, and mortality. Results A total of 16 of 397 (4.0%) patients developed SERF at a median of 5 months after stent placement (range 0.4-53 months) including 6 of 94 (6%), 10 of 71 (14%), and 0 of 232 (0%) of those with lesions in the proximal, middle, and distal esophagus, respectively (overall P < .001). SERF occurred in 10% of those with proximal and mid-esophageal lesions, including 14% with benign strictures, 9% with malignant strictures, and none with other indications for SES placement ( P = .27). The risk was highest (18%) in patients with benign anastomotic strictures. Risk factors for development of SERF included a higher Charlson comorbidity index score (odds ratio OR 1.47 for every 1-point increase; P = .04) and history of radiation therapy (OR 9.41; P = .03). Morbidity associated with SERF included need for lifelong feeding tubes in 11 of 22 (50%) and/or tracheostomy or mechanical ventilation in 5 of 22 (23%). Median survival after diagnosis was 4.5 months (range 0.35-67), and 7 patients survived less than 30 days. Limitations Retrospective design, limited statistical power. Conclusion SERF is a morbid complication of SES placement for strictures of the proximal and mid-esophagus. The dominant risk factors for development of SERF are prior radiation therapy and comorbidity score.
We tested the hypothesis that human immunodeficiency virus (HIV)–infected adults have a specific defect in anti-pneumococcal capsular polysaccharide (Pn-specific) immunoglobulin (Ig) in fluid ...obtained from the lower respiratory tract. Higher levels of total IgG and IgM were present in bronchoalveolar lavage samples from HIV-infected subjects than in those from HIV-uninfected subjects. Pn-specific IgG and IgM in bronchoalveolar lavage samples were not significantly different between HIV-infected and -uninfected subjects. After pneumococcal infection, HIV-infected patients had higher bronchoalveolar lavage levels of Pn-specific IgG than HIV-infected patients without recent infection (geometric means, 387 vs. 30 ng/mL, P=.001)
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